His son-in-law, a classmate of Facebook founder Mark Zuckerberg, tried to set up a meeting between the two men.

Rubenstein didn't take the meeting.

"I asked myself, what are the chances of this guy becoming the next Bill Gates?" Rubenstein said. "So now I have to work for a living."

I'm sure many folks at Milken will be talking about Facebook. Is it the new Google ? Or is it Pets.com, the disgraced icon of the Internet bubble?

Last year, the "smart money" folks were already worried about Internet stock prices. Many openly mocked Groupon , for example. But with Internet stocks still running hot, will the skepticism remain? Or will the big money guys jump on board the good ship Social Media?